Effects of AlGaN Back Barrier on AlN/GaN-on-Silicon High-Electron-Mobility Transistors

Abstract

In this work, the effects of an AlGaN back barrier in the dc and RF performances of AlN/GaN high-electron-mobility transistors (HEMTs) grown on 100 mm Si substrates have been investigated. It is shown that the outstanding dc performance in highly scaled AlN/GaN-on-Si HEMTs can be fully preserved when introducing an AlGaN back barrier while significantly reducing the sub-threshold drain leakage current and enhancing the RF performance by the reduction of short-channel effects. Therefore, the AlN/GaN/AlGaN double heterostructure enables high-aspect-ratio devices generating extremely high current density, low leakage current, and high voltage operation.

High PAE high reliability AlN/GaN double heterostructure

“…Recently, we have developed in this frame a novel technology based on an AlN/GaN/AlGaN-on-Si double heterostructure. It was demonstrated that a low leakage current, a high transconductance, and an extremely high current density can be achieved simultaneously using this double heterostructure [1][2][3][4][5]. Furthermore, as can be seen in Fig.…”

High Electron Confinement under High Electric Field in RF GaN-on-Silicon HEMTs

“…current [7,8]. On top of the material quality, the in situ grown SiN cap layer has been a key feature for controlling the surface parasitic leakage current and achieving high performance [9][10][11], namely by preventing the strain relaxation of the barrier layer. In this paper, we report on the high breakdown voltage in highly scaled GaN transistors grown on a silicon substrate, showing that all the above-mentioned issues can be overcome in these emerging types of devices.…”

“…In this frame, we have demonstrated the possibility of preventing gate tunneling through highly scaled Aluminum Nitride (AlN) barrier thickness (below 5 nm) by showing an extremely low gate leakage current [7,8]. On top of the material quality, the in situ grown SiN cap layer has been a key feature for controlling the surface parasitic leakage current and achieving high performance [9][10][11], namely by preventing the strain relaxation of the barrier layer.…”

Trends in the Development of the Epitaxial Nitride Compounds Technology

“…Поэтому в последние 5 лет интенсивное раз-витие получило третье из упомянутых выше тех-нологических направлений создания нитридных гетероструктур -разработка структур на подложке кремния [3][4][5][6][7]. Применение Si в качестве подложеч-ного материала рассматривается как чрезвычайно перспективное направление в силу того, что потен-циал данной технологии гетероструктур GaN/Si обе-спечивается следующими факторами:…”